Slide projector for use with straight and circular slide trays

ABSTRACT

A slide projector whose housing is formed with a tunnel extending in parallelism with the optical axis of the projection lens for reception of stepwise advancing straight slide trays, and with a pocket which communicates with a median portion of the tunnel and permits insertion of a circular slide tray upon removal of a straight tray. The bottom wall of the tunnel is provided with two segment-shaped cams which can enter parallel channels provided in the undersides of straight trays or concentric annular channels in the undersides of circular trays to lift slides from a lower level to a higher level. The thus raised slides are located at a level above a straight or cylindrical panel of a straight or circular tray over which the slide changer must transport the slides toward viewing position. The circular trays are indexible about a vertical axis.

54] SLIDE PROJECTOR FOR USE WITH STRAIGHT AND CIRCULAR SLIDE TRAYS [72]Inventor: Helmut Rube, Endersbach, Germany 1 [73] Assignee: Robert BoschElektronik und Photokino GmbH, Stuttgart-Unterturkheun, Germany [22]Filed: July 19,1968

[21] Appl. No.1 746,123

[30] Foreign Application Priority Aug. 18, 1967 Germany ..P 15 72 584.5

[52] US. Cl. "353/1 17 [51] Int. Cl. ..G03b 23/06 [58] Field of Search..353/l16, 117,103, 114, 107, 353/104, 118, 115

[56] References Cited UNITEDSTATESPA'I'ENTS 3,118,341 1/1964 Weiss..1..353/11s 3,233,511 2/1966 -D6g ..353/117 3,409,353 11/1968 211111161.353/117 11/1968 Rube ..353/1 15 R26,619 7/1969 Hall ..353/l17 OTHERPUBLICATIONS Liesegang projector Literature.

Primary Examiner-Leonard Forman Assistant Examiner-A. J. MirabitoAttorney-Michael S. Striker [57] ABSTRACT 1 A slide projector whosehousing is formed with a tunnel extending in parallelism with theoptical axis of the projection lens for reception of stepwise advancingstraight slide trays, and with a pocket which communicates with a medianportion of the tunnel and permits insertion of a circular slide trayupon removal of a straight tray. The bottom wall of the tunnel isprovided with two segment-shaped cams which can enter parallel channelsprovided in the undersides of straight trays or concentric annularchannels in the undersides of circular trays to lift slides from a lowerlevel to a higher level. The thus raised slides are located at a levelabove a straight or cylindrical panel of a straight or circular trayover which the: slide changer must transport the slides toward viewingposition. The circular trays are indexible about a vertical axis.

9 Claims, 7 Drawing, Figures PATENTEDHEB 5 m2 3; 704 343 m ArroezvfSLIDE PROJECTOR FOR USE WITH STRAIGHT AND CIRCULAR SLIDE TRAYSBACKGROUND OF THE INVENTION The present invention relates to slideprojectors in general, and more particularly to slide projectorarrangements wherein the housing of the slide projector can'accept andsupport straight (bar-shaped) or circular slide trays. Still moreparticularly, the invention relates to improvements in slide projectorarrangements of the type having a bottom panel provided with a straightchannel which communicates with the slide compartments and extends intothe partitions between such compartments so that it can permit entry ofa stationary ramp provided'in the projector housing and serving to liftslides into the range of a slide changer. Each straight magazine whichis to beused in such slide projectors is normally provided with arelatively high and. a relatively low side panel which latter must becleared by a raised slide in order that the thus raised slide can betransported toward viewing position. The purpose of the side panels isto prevent lateral displacement of slides in the compartments whichextend between the two side panels. Also, such side panels prevent theslides from leaving the respective compartments in response tounintentional tilting of the straight trayduring insertion into orduring removal from the housing of the slide projector, or in storage.

The aforementioned ramp or cam in the slide projector which is disclosedin German Pat. No. 1,033,928 engages the central portion of the loweredge of a slide mount to prevent tilting of the slide during lifting andto thus avoid damage to the slide during engagement with and duringtransport by the slide changer. Certain other types of straight traysare provided with a wider and with a narrower channel the former ofwhich can accommodate a wider ramp and the latter of which receives anarrower-ramp. Such pairwise ramps'also serve as a means for lifting theslides without appreciable tilting during indexing of the tray withreference to the housing of the slide projector.

A serious drawback of all conventional slide projectors which employlifting ramps is that their housings can accommodate or support straighttrays but that such housings are not suited for use with circular slidetrays. As a rule, the ramps are elongated straight elements consistingof metal or plastic and, therefore, they could not enter a circularchannel which would have to be provided in a'circular slide tray.

SUMMARY OF THE INVENTION It is an important object of my presentinvention to provide an arrangement which includes a slide projectorcapable of being'used withdifferent types of slide trays and to providethe housing of the slide projector with novel lifting means which iscapable of raising slides in circular or straight trays.

Another object of the invention is to provide a slide projector whichcan be used with certain presently known types of straight trays as wellas with novel circular slide trays.

A further object of the invention is to provide a slide projector whosehousing can accommodate straight slide trays as well as circular slidetrays which are indexible about a vertical or nearly vertical axis sothat they need not extend above the housing or extend only slightlybeyond the topmost part of such housing.

Still another object of the invention is to provide circular slide trayswhich can be utilized in slide projectors of the above outlinedcharacter.

An ancillary object of the invention is to provide a novel liftingdevice which can be utilized in the housing of a versatile slideprojector to raise slides from compartments in circular trays or fromcompartments of straight trays.

A further object of the invention is to provide a lifting device whichcan lift slides in circular or straight trays without any tilting and toa level at which a raised slide can be transported without anyinterference toward and away from viewing position.

The improved arrangement comprises a slide projector including ahousing, slide changer means installed in the housing for movement(either by hand or by means of a motor) between first and secondpositions to thereby transport slides between thecompartments of a slidetray and a viewing position, and lifting means provided in the housingat a level below the slide changer means and having faces arranged toraise successive slides stored in a tray which is indexibly insertedinto the housing from a lower level to a higher level. The outline ofthe lifting means is such that it can enter at least one straightchannel or slot provided at the underside of a straight tray uponinsertion of the straight tray into the housing of the slide projectoror into at least one annular channel or slot provided in the undersideof a circular tray when the latter is inserted into the housing uponremoval of the straight tray.

In accordance with a presently preferred embodiment of my invention, thelifting means comprises two fixed cams or ramps which extend upwardlyfrom a bottom wall of the housing and each of which has an outlineresembling that of the segment of a circle. The faces of each campreferably include .a centrally located horizontal top face and two endfaces which are inclined downwardly in opposite directions and flank therespective top face. The end faces guide the lower edges of slide mountsduring movement toward or off the respective top faces.

The novel features which are considered as characteristic of theinvention are set forth in particular in the appended claims. Theimproved arrangement itself, however, both as to its construction andits mode of operation, together with additional features and advantagesthereof, will be best understoodupon perusal of the following detaileddescription of a specific embodiment with reference to the accompanyingdrawing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of anarrangement which embodies the invention, a circular slide tray beingshown in operative position in the housing of the slide projector;

FIG. 2 is an enlarged fragmentary transverse vertical sectional view ofthe structure shown in FIG. 1;

FIG. 3 is a horizontal sectional view substantially as seen in directionof arrows from the line III-III of FIG. 2;

FIG. 4 is a fragmentary transverse vertical sectional view of thehousing in the slide projector and of a straight slide tray which isinserted into the tunne defined by the projector housing;

FIG. Sis a horizontal sectional view substantially as seen in thedirection of arrows from the line VV of FIG. 4;

FIG. 6 is an enlarged sectional view substantially as seenin thedirection of arrows from the line VI-VI of FIG. and

FIG. 7 is an enlarged perspective view of a portion of the structureshown in FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1,illustrates anarrangement which comprises a slide projector and a circular slide tray28. The slide projector includes a housing'l having legs 2 and a frontwall 3 supporting a-lens barrel 4. The housing 1 is further providedwith a straight horizontal passage or tunnel 5 which is parallel to theoptical axis of the projection lens and serves, among others, to guide astraight slide tray 6,-shown in FIGS. 4 and 5, which can be used as asubstitute for the circular tray 28. The straight tray 6 preferablyconsists of synthetic plastic material and comprises a bottom panel 7, arelatively high side panel 8, and a relatively low side panel fonning arack 9 provided with teeth 10 which can mesh with the teeth of anindexing or advancing gear 11 mounted in the housing 1. The tray 6further comprises a set of partitions 13 which define compartments 12for slides 14. The slides 14 can be transported between the compartments12 and a viewing position in which they extend across the optical axis.The means for transporting the slides comprises a slide changer 16 whichis reciprocable in directions indicated by a doubleheaded arrow 15. Themeans for actuating the slide changer 16 forms no part of the presentinvention.

The housing 1 further comprises a bottom wall 17 which extends at alevel below the tunnel 5 and is affixed to a base plate 18 by recessedscrews 19. The bottom wall 17 supports an upwardly extending shaft 20for the aforementioned gear 1 l.

The bottom panel 7 of the straight tray 6 is formed with twolongitudinally extending parallel slots or channels 21, 22 which extendwell into thelower portions of the partitions 13 (see FIG. 4). When thetray 6 is inserted through the rear end of the tunnel 5, the channels21, 22 respectively accommodate two lifting cams or ramps 23, 24. Thesecams or ramps are respectively formed with centrally located flat topfaces 25, 26 which are disposed in the region of the slide changer 16 sothat they can maintain in raised position that slide 14 which is to betransported to viewing position. The common plane of the top faces 25,26 is located at the level of or above the topmost part of the lowerside panel or rack 9. The ramps are further provided with inclined endfaces 23a, 23b and 24a, 24b which slope gradually in opposite directionsfrom and flank the corresponding top faces 25, 26. This is best shown inFIGS. 6 and 7.

Referring again to FIG. 1, the right-hand side wall 30 of the housing 1is provided-with a relatively shallow recess 3b which accommodates a rowof actuating buttons 30 serving to initiate and terminate variousoperations of the slide projector, such asstarting and arresting themotor which drives the slide changer 16 and the gear 11, turning on oroff the projection lamp, and others. In addition, the side wall 30 isformed with a relatively deep rectangular pocket 27 which communicateswith a median portion of the tunnel 5 and permits insertion'of thecircular slide tray 28 in such a way that, when properly inserted, thetray 28 is indexible about a vertical axis. As shown in FIG. 2, thehousing 1 has an internal side wall 29 which is adjacent to one side ofthe tunnel 5 and is provided with an opening or cutout which establishescommunication between the pocket 27 and the tunnel 5 and permitsintroduction of a portion of the circular tray 28 into the medianportion of the tunnel. The tray 28 comprises a disk-shaped bottom panel30, a relatively high cylindrical inner panel or shell 31 and arelativelylow cylindrical outer panel or shell 32. Thin partitions 35extend radially between the shells 31, 32 and define an annulus ofradial compartments 34 for slides 33.

The bottom panel 30 of the tray 28 has a centrally located opening 36which can accommodate a locating or positioning projection 37 here shownas -a stub extending upwardly from the bottom wall 17 of the housing 1and being accommodated in the pocket 27. The stub 37 has an inclinedfacet or flat 37a so that the cross-sectional area of its tip isconsiderably smaller than the cross-sectional area of the lower end ofthe stub. This facilitates insertion of the stub into the opening 36. Itwill be noted that the flat 37a faces the open side of the pocket 27. Asshown in FIG. 5, the upper side of the bottom wall 17 is further formedwith an arcuate groove 38 which can receive a portion of a circular rim39, extending downwardly from the bottom panel 30 of the circular tray.28, when the latter is properly inserted into the pocket 27 so that theopening 36 receives the stub 37. The rim 39 has an annulus of teeth 40forming an external gear which meshes with an indexing gear 41 on thehousing 1. The gear 41 is coaxial and integral with the gear 11 and canrotate therewith on the shaft 20.

The pocket 27 further accommodates a bracket or retainer 42 for a leafspring 43 which carries a rounded biasing or pressure transmittingmember 44. The latter can engage the side panel 8 of the straight tray 6when this tray extends into the tunnel 5 so that the spring 43 thenbiases the teeth 10 of the lower side panel or rack 9 into mesh with theteeth of the gear 11. The parts 42-44 form a portion of a guide assemblyfor the tray 6 and cooperate with two protuberances 46, 47 (shown inFIG. 5) to properly guide the tray 6 in the region where the trayadvances along the pocket 27. The protuberances 46, 47 are provided on asecond internal side wall 45 of the housing 1; this side wall 45 isadjacent to the other side of the tunnel 5, i.e., it is located oppositethe side wall 29. When the straight tray 6 is replaced with the circulartray 28, the biasing member 44 engages the lower portion of the innercylindrical shell 31. to bias the teeth 40 into mesh with the teeth ofthe indexing gear 41. The parts 42-44 then extend into a circular groove48 (FIG. 2) provided in the underside of the bottom panel 30 radiallyinwardly of the shell 31. An important advantage of the parts 42-44 isthat they insure proper mesh between the teeth 40 and the teeth ofindexing gear 41 even if the diameter of the opening 36 exceedsconsiderably the maximum diameter of the positioning stub 37. This isdesirable to. facilitate insertion and centering of the circular tray28.

The bottom panel 30 of the circular tray 28 is further formed with tworelatively deep concentric annular slots or channels 49, 50 which aredisposed between the cylindrical shells 31, 32 and extend well into thelower portions of the partitions 35. This is best shown in theright-hand part of FIG. 2. The distance between the channels or slots49, 50 is the same as that between the channels or slots 21, 22 of thestraight tray 6, and the cross-sectional areas of the channels 49, 50respectively equal the cross-sectional areas of the channels 21, 22.Thus, that portion of the circular tray 28 which extends into the tunnel5 is similar to the corresponding portion of the straight tray 6. Thechannels 49, 50 can respectively accommodate the cams or ramps 23, 24(see FIGS. 2 and 3) so that the top faces 25, 26 of these ramps canraise above .the outer panel or shell 32 that slide 33 which is about tobe transported to viewing position. The outlines of the ramps 23, 24 arebest shown in-FlGS. 3 and 5. it will be seen that these outlines'areselected with a view to insure entry of the ramps into the channels 21,22 or 49, 50 and to further insure that the top faces 25, 26 of theramps can lift slides 14 or 33. Furthermore, the configuration ofinclined end faces 23a, 23b and24a, 24b on the ramps 23, 24 is such thatthey can gradually lift and lower the slides 14 or 33 in untiltedpositions, i.e., so that the bottom edges of the slide mounts are alwaysparallel to the top face of the bottom plate 17. The outlines of theramps 23, 24 resemble segments of circles having different radii. Theradius of curvature of the arcuate (convex) outer side 51, of the ramp23 is slightly less than the maximum radius of the, channel 49, and theradius of curvature of the convex outer side 52 of the ramp 24 isslightly less than the maximum radius of the inner channel 50 (see FIG.3). The tips 53, 55 of the ramp 23 are disposed at the ends of a flatinner-side of this ramp which inner side is parallel to the tunnel 5.The same applies for the tips 54, 56of the ramp 24. The tips 33, 54 and55, 56 are respectively located in two planes which extend radially fromthe axis of the positioning stub 37. In otherwords, the ramp 24 isshorter than the ramp 23, as considered in the circumferential directionof the circular tray 28 in fully inserted position. The end faces 24a,24b of the ramp 24 are somewhat steeper than the end faces 23a, 23b ofthe ramp 23 (see FIG. 6). This insures that the lower edge of the mountof a slide 33 is held in a horizontal plane in response to successiveindexing movements of the circular tray 28. In other words, suchdifference in the inclination of end faces 23a, 23b and 24a, 24b insuresthat the lower edge of a slide mount engages such portions of end faces23a, 24a or 23b, 24b which are located at the same level.

The operation is as follows:

If the user wishes to project the images of a set of slides 14 which arestored in a straight tray 6, the circular tray 28 is removed and thetray 6 is inserted through the rear end of the tunnel 5 so that theteeth 101 of its side panel or rack 9 engage the teeth of the gear 11.The rack 9 is then adjacent to the internal side wall 45 of the housing1 (FIG. 5). When the gear 11 meshes with the raclr 9, at least one ofthe foremost slides 14 in the tray 6 is already lifted by the inclinedend faces 23a, 24a of the ramps 23, 24 because these ramps then extendinto the channels 21, 22. The tip 55 of the longer ramp 23 engages themedian portion of the lower edge of the mount of the foremost slide 14and such mount is thereupon moved to a higher level while remaining in ahorizontal position. The arrangement is preferably such that theforemost slide 14 already rests on the top faces 25, 26 when the leadingend of the rack 9 begins to mesh with the gear 11. As stated before, thelower edge of the mount of the foremost slide l4'is then raised to alevel above the rack 9 (see FIG. 4'). This enables the slide changer 16to transport the foremost slide 14 to viewing position behind the lensbarrel 4 and to thereupon return the foremost slide intothecorresponding compartment 12. The gear 1 l is then caused to advance thetray 6 by a step so as to place the next slide 14 into regstry with theslide changer 16 whereby the next slide rests on the central portions ofthe top faces 25, 26 at a level above the rack 9. Slides 14 which arereturned into the compartments l2 thereupon slide downwardly along theinclined faces 23b, 24b and beyond the rear tips 53, 54 of the ramps 23,24 to come to rest on the bottom panel 7 of the tray 6.

If the straight tray 6 is to be replaced with the circular tray 28, thetray 6 is withdrawn through the front end of the tunnel 5 so that theuser can insert the tray 28 through the pocket 27 in horizontal ornearly horizontal position and in such a way that the bottom panel 30 ofthe tray 28 is located at a level slightly above the tip of thepositioning stub 37. When the opening 36 in the bottom panel 36registers with the stub 37, the tray 28 can descend by gravity and therim 39 enters the arcuate groove 38 of the bottom plate 17 so that theteeth 40 below the shell 32 mesh with the teeth of the indexing gear 41(FIG. 2 or 3). At the same time, the ramps 23, 24 enter the adjoiningslides 33. As stated before, the top faces 25, 26 are located at thesame level so that any slide 33 which comes to rest on these top facesis automatically held in a raised position in which its lower edge ishorizontal. The same holds true for those slides whose lower edgesrespectively rest on the inclined end faces 23a, 24a or 23b, 24b. Thisis due to the aforementioned difference in inclination of such end faces(see FlG. 6). The operation of the slide projector is more secure andmore reliable if all the slides are held in positions in which theirlower edges remain horizontal.

When the motor of the slide projector is started, the slide changer 16engages that raised slide 33 which is in registry therewith and rests onthe central portions of the top faces 25, 26. The slide changer 16 thenmoves such slide at a level above the relatively low outer shell 32 andtoward viewing position. When the projection of the image of the firstslide 33 is completed, the slide changer 16 returns it into thecorresponding compartment 34 and the gear 41 indexes the tray 28 by astep so as to move the next-following slide 33 into registry with theslide changer. The same procedure is repeated until the operator decidesto withdraw the tray 28 or until after the viewing of all slides 33 iscompleted.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featureswhich fairly constitute essential characteristics of the generic andspecific aspects of my contribution to the art and, therefore, suchadaptations should and are intended to be comprehended within themeaning and range of equivalence of the claims.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims:

1. In an arrangement of the character indicated, a combinationcomprising a straight slide tray having transversely extendingcompartments for slides and an underside provided with a pair ofstraight parallel channels communicating with said compartments; acircular slide tray having radially extending compartments for slidesand an underside provided with a pair of concentric" annular channelscommunicating with said last mentioned compartments; and a slideprojector including a housing having first and second passagesrespectively arranged to receive said straight and circular trays, saidpassages having a common portion so that said first passage is free toreceive said straight tray only when said circular tray is removed fromsaid second passage and vice versa, slide changer means installed insaid housing for movement between first and second vpositions to therebytransport slides between those compartments of one of said trays whichare located in said common portion of said passages and a viewingposition, and lifting means comprising a pair of cams provided in saidcommon portion of said passages below said slide changer means andhaving faces arranged to raise from a lower level to a higher levelsuccessive slides in that one of said trays which is inserted into therespective passage, the positions of said cams being such that eachthereof enters a different one of said straight channels from below saidchannels upon insertion of said straight tray into said first passageand a different one of said annular channels on insertion of saidcircular tray into said second passage, portions of said annularchannels and said straight channels being disposed in said commonportion of said passages when said straight and circular trays arealternatively used,

said circular tray being indexible about a substantially vertical axisand said straight tray being indexible lengthwise upon insertion intothe respective passage of said housing.

2. A combination as defined in claim 1, wherein said first passage is astraight tunnel and said second passage is an open-sided pocket, saidhousing including a bottom wall having a portion located below saidcommon portion of said passages and said cams being provided on saidportion of said bottom wall.

3. A combination as defined in claim 1, wherein at least one of saidcams has a substantially straight side and a convex side.

4. A combination as defined in claim 3, wherein the faces of said caminclude a substantially horizontal top face on which a slide rests inthe raisedposition thereof and a pair of end faces inclined downwardlyin opposite directions and flanking said top face.

5. A combination as defined in claim 1, wherein said straight tray has aside panel which is located at a level fifim lillffiell is fnill filrl liiiflfg sfiffi iillllfi' slide changer means can transport such slideover the side panel toward said viewing position.

6. A combination as defined in claim 1, wherein said circular tray has arelatively low cylindrical outer shell located at a level below a slidewhich is lifted by said cams to raised position in response to insertionof the circular tray into said housing so that the slide changer meanscan move the thus raised slide over said outer shell during transport toviewing position.

7. A combination as defined in claim 1, wherein each of said camscomprises a top face located at the level of the top face of the othercam and a pair of end faces inclined downwardly in opposite directionsand flanking the respective top face to effect gradual lifting andlowering of slides onto and from said top faces in response to stepwiseindexing of the respective tray.

8. A combination as defined in claim 7, wherein the inclination of endfaces on one of said cams deviates from the inclination of end faces onthe other cam.

9. A combination as defined in claim 1, wherein the outlines of saidcams are segments of circles having different radii.

1. In an arrangement of the character indicated, a combination comprising a straight slide tray having transversely extending compartments for slides and an underside provided with a pair of straight parallel channels communicating with said compartments; a circular slide tray having radially extending compartments for slides and an underside provided with a pair of concentric annular channels communicating with said last mentioned compartments; and a slide projector including a housing having first and second passages respectively arranged to receive said straight and circular trays, said passages having a common portion so that said first passage is free to receive said straight tray only when said circular tray is removed from said second passage and vice versa, slide changer means installed in said housing for movement between first and second positions to thereby transport slides between those compartments of one of said trays which are located in said common portion of said passages and a viewing position, and lifting means comprising a pair of cams provided in said common portion of said passages below said slide changer means and having faces arranged to raise from a lower level to a higher level successive slides in that one of said trays which is inserted into the respective passage, the positions of said cams being such that each thereof enters a different one of said straight channels from below said channels upon insertion of said straigHt tray into said first passage and a different one of said annular channels on insertion of said circular tray into said second passage, portions of said annular channels and said straight channels being disposed in said common portion of said passages when said straight and circular trays are alternatively used, said circular tray being indexible about a substantially vertical axis and said straight tray being indexible lengthwise upon insertion into the respective passage of said housing.
 2. A combination as defined in claim 1, wherein said first passage is a straight tunnel and said second passage is an open-sided pocket, said housing including a bottom wall having a portion located below said common portion of said passages and said cams being provided on said portion of said bottom wall.
 3. A combination as defined in claim 1, wherein at least one of said cams has a substantially straight side and a convex side.
 4. A combination as defined in claim 3, wherein the faces of said cam include a substantially horizontal top face on which a slide rests in the raised position thereof and a pair of end faces inclined downwardly in opposite directions and flanking said top face.
 5. A combination as defined in claim 1, wherein said straight tray has a side panel which is located at a level below a slide which is lifted to its raised position when the straight tray is inserted into said housing so that the slide changer means can transport such slide over the side panel toward said viewing position.
 6. A combination as defined in claim 1, wherein said circular tray has a relatively low cylindrical outer shell located at a level below a slide which is lifted by said cams to raised position in response to insertion of the circular tray into said housing so that the slide changer means can move the thus raised slide over said outer shell during transport to viewing position.
 7. A combination as defined in claim 1, wherein each of said cams comprises a top face located at the level of the top face of the other cam and a pair of end faces inclined downwardly in opposite directions and flanking the respective top face to effect gradual lifting and lowering of slides onto and from said top faces in response to stepwise indexing of the respective tray.
 8. A combination as defined in claim 7, wherein the inclination of end faces on one of said cams deviates from the inclination of end faces on the other cam.
 9. A combination as defined in claim 1, wherein the outlines of said cams are segments of circles having different radii. 